Carton folding machine



Oct. 8, 1957 E. LARSEN CARTON FOLDING MACHINE 12 Sheets-Sheet 1 Filed May 18, 1954 INVENTOR 7L A AlQjE/V ATTORNEY Oct. 8, 1957 E. LARSEN 2,808,766

' CARTON FOLDING MACHINE Filed May 18, 1954 12 Sheets-Sheet 2 2 3 INVENTOR EARL LAESE/V ATTORNEY Oct. 8, 1957 LARSEN CARTON FOLDING MACHINE Filed May 18, 1954 12 Sheets-Sheet 3 J m% 0% l x f Y H QN Q\ F W o v w a m @m. v 7 m Q B NA \V MN m JLJVQ T n d ww wwwnfi Sm Oct. 8, 1957 E. LARSEN CARTON FOLDING MACHINE 12 Sheets-Sheet 4 Filed May 18, 1954 INVENTOR fA/QL L/l/QSE/V ATTO RN EY 1 Oct. 8, 1957 E. LARSEN CARTON FOLDING MACHINE 12 Sheets-Sheet 5 Filed May 18, 1954 vm N INVENTOR 62/?4 ./wsf/v ATTORNEY (jet. 8, 1957 E. LARSEN 2,808,766

CARTON FOLDING MACHINE Oct. 8, 1957 I E. LARSEN 2,808,766

CARTON FOLDING MACHINE 12 Sheets-Sheet 7 Filed May 18, 1954 INVENTOR lE/WL 4/0955 ATTORNEY Oct. 8, 1957 E. LARSEN 2,803,765

CARTON FOLDING MACHINE Filed May 18, 1954 12 Sheets-Sheet 8 EARL LAESE/V ATTORNEY Oct. 8, 1957 E. LARSEN 2,808,766

' CARTON FOLDING MACHINE Filed May 18,-.1954 I 12 Sheets-Sheet 9 INVENTOR EARL L A ejf/v.

' ATTORN EY Oct. 8, 1957 E. LARSEN 2,808,766

CARTON FOLDING MACHINE Filed May 18, 1954 12 Sheets-Sheet 10 INVENTOR E424 4AA=5N ATTORNEY Oct. 8, 1957 E. LARSEN 2,808,766

CARTON FOLDING MACHINE Filed May 18, 1954 12 Sheets-Sheet 11 INVENTOR 5 5424 A ARSE/V.

ATTORNEY Oct. 8, 1957 E. LARSEN ,808,

CARTON FOLDING MACHINE Filed May 18, 1954 l2 Sheets-Sheet 12 INVENTOR 54/94 A/PSF/ gy/a1 1% ATTORNEY United States Patent i CARTON FOLDING MACHINE Earl Larsen, Mineola, N. Y., assignor to Delson Candy Company, New York, N. Y., a corporation of New York Application May 18, 1954, Serial No. 430,570

14 Claims. (Cl. 93-49) This invention relates to machines for erecting preformed card board blanks into cartons or boxes ready for filling and particularly to machines which are adapted to fold blanks into boxes having sides with end flaps that are attached to the sides and overlap and interlock. Additionally the boxes may have inner end flaps attached to the bottom, and one of the sides may have an extension forming a cover.

One of the principal objects of the invention is to provide a machine for this purpose which will be reliable in its operation and will be simple and inexpensive. Other ancillary objects are economic speed of operation and compactness and limitation in size within industrial needs. Other objects will appear from the description which follows.

The invention contemplates a motor driven mechanical structure in which blanks are fed in succession from the bottom of a stack in a holder or magazine onto a table which has a blank receiving station and a blank folding station. Two longitudinally spaced fingers which preferably are in laterally spaced pairs project up through the table and reciprocate in slots, the rear finger or fingers pushing the delivered blanks from the receiving to the folding station and the forward finger or fingers ejecting the folded boxes. Means are provided to cause the forward finger or fingers to disappear below the table top for their rearward travel and to emerge above the table top at the conclusion of their rearward movement.

The invention contemplates suction means for picking the blanks from the bottom of the stack and delivering them to the receiving station. Specifically the delivery means is in the form of suction cups on an invertible head which is moved up and down by motor driven crank means and inverts the cups from an up position at the top of the travel to a down position at the bottom of the travel. A suction pump is timed in its operation to produce suction in the cups upon their contact with the bottom blank in the stack and this suction is maintained until the cups overhang the receiving station in inverted position when a tappet valve is operated and the suction broken. The reversal of the pump at this instant serves to produce pressure on the cups and forcibly deliver the blank.

To fold the blank at the folding station the invention contemplates the use of orbitally moving folding fingers which are carried by shafts rotatively mounted over the folding station and geared to operate the fingers in properly timed relation. Preferably they all rotate at the same angular speed and the timing is obtained by the relative angular setting of the fingers.

There will be four shafts forming a quadrangle enclosing the folding station if the box is without a cover. Fingers on the two side shafts will raise the sides of the box and the end flaps will be controlled by fingers on the end shafts. The effecting of the interlock of the two outer flaps on each-end is a feature of the invention in accordance with which a tongue on one flap is caused to enter a on 2,808,766 Patented Oct. 8, 1957 slit in the other flap "as an incident of the folding. To accomplish this outwardly curved fingers on the adjacent side shaft are positioned to wipe in the slit-containing end flaps as that side is raised, and a foot shaped member on each end shaft folds in the other end' flap as the other side is raised and bears against the slitted flap to open the slit, at the same time guiding the tongue into the slit as the flap on the other side is moved into overlapping position.

The blanks are introduced so that the side having the tongue-bearing flaps leads and is on the outer or exit side of the folding station. A shaft on that side would of course interfere with the ejection of a formed box having an upstanding cover. Hence it is contemplated that for boxes having attached covers the shaft on the exit side of the station will be omitted and fingers will be provided on the end shafts to raise that side element of the blanks.

There are other features of construction within the comprehension of the invention, as will appear from the following description of one embodiment of the invention. For this purpose reference is made to the accompanying drawings in which Fig. 1 is a side elevation of the upper portion of an apparatus embodying the invention, being the portion which effects the delivery and folding of the blanks and the ejection of the formed boxes, this figure being a partial section as indicated by the line 1-1 of Fig. 3;

Fig. 2 is an end elevation, partly in section, of the complete machine as viewed from the right of Fig. 1;

Fig. 3 is a sectional plan on the plane of line 3-3 of Fig. 1;

Fig. 4 is a sectional plan on the plane of line 4-4 of Fig. 1;

Fig. 5 is a partial longitudinal vertical sectional elevation on the plane of line 5-5 of Fig. 2;

Fig. 6 is an enlarged vertical section of the mechanism shown in Fig. 1, taken on the plane of line 66 of Fig. 1;

Fig. 7 is an enlarged fragmentary plan of the left end shaft and parts carried thereby and operatively related thereto, as shown in Fig. 3, the operating members for the hold-down plunger being shown in section;

Fig. 8 is a view similar to Fig. 7 but showing the folding mechanism slightly advanced beyond the position of Fig. 7; v

Fig. 9 is an enlarged fragmentary elevation of the parts shown in Figs. 7 and 8, being taken on the plane indicated by the line 9-9 in Fig. 8;

Fig. 10 is a vertical section of the same, being taken on the plane of line 10-10 of Fig. 9;

Fig. 11 is a view similar to Fig. 9 but showing the mechanism advanced to a further stage of operation;

Fig. 12 is a vertical section of the same being taken on the plane of line 12-12 of Fig. 11;

Fig. 13 is a view similar to Fig. 11 but showing the mechanism advanced to a still further stage of operation;

Fig. 14 is a vertical section of the same, being taken on the plane of line 14-14 of Fig. 13;

Fig. 15 is a view similar to Fig. 13 but omitting the mechanism below the table and showing the folding mechanism in its final stage of folding;

Fig. 16 is a fragmentary horizontal sectional plan or face view in the folding station in Fig. 3, and Figs. 17 to 21, inclusive, show the blank and the successive stages of folding, the finished box being shown in Fig. 21.

The blank, which is identified generally by the letter B is preformed with folding crease lines, the component elements comprising the two sides S and S the bottom B bottom end flaps E and E attached to the bottom, side end flaps E and E attached to side S and side end flaps E and E attached to side S The side end flaps E and E are each provided with a slit K in their top edges, and each side end fiap E and E has its inner free corner cut away to form a curved edge tongue T that enters into the slit K in the slitted flap on its end in the final step of folding and thus interlocks the two side end flaps together and secures the box in erected condition. The crease lines on which the elements fold are indicated by broken lines in flat representation and in full lines in folded or partially folded representation.

The steps in folding preformed blanks by the machine are illustrated in Figs. 17 to 21. The blank having been fed in flat to the folding station, as shown in Fig. 3, first has its bottom end flaps E and E raised, as shown in Fig. 17. Next the side S is raised, an intermediate position being shown in Fig. 17 and the fully erected position being shown in Fig. 18.

As this side S is raised, the attached end flaps E and E are wiped or turned in, an intermediate position of these end flaps being shown in Fig. 18 and their final position being shown in Fig. 19.

Next the side S is raised, progressive intermediate positions being shown in Figs. 19 and 20. At the same time the side end flaps E and E are turned in and pressure is exerted onto the upper left corner of flaps E and E to openthe slits K as shown in Fig. 20. The tongues T are directed into the open slits as shown in Fig. 20, and the final erecting movement of the side S forces the tongue home to locking condition, as shown in Fig. 21. The bottom edge of the tongues is convexly curved and hence provides a notch at the inner corner which receives the bottom of the slit. The convex curvature of the bottom edge of the tongue makes it necessary slightly to raise the flaps E and E to unlock them and securely interlocks the two overlapping outer flaps. The final erected condition is shown in Fig. 21.

The frame of the machine which is shown particularly in Figs. 1 to 6, inclusive, consists of structural steel members including angle corner columns 1, 2, 3 and 4 and various longitudinal and transverse connecting and supporting members which will appear as the description progresses. Corner columns 1 and 4- are connected at their tops by angle frame piece 5 and columns 2 and 3 are similarly connected at their tops by frame piece 5a. Table supporting frame members comprise transverse angle members 6 and 7 joining columns 1, 2 and 3, 4, respectively, at an intermediate level substantially one-third of the distance from the top of the frame, and side angle frame members 8 and 9 connecting the left and right ends, respectively, of members 6 and 7 (see Fig. 1). As shown these members 6, 7, 8 and 9 are integrally united, as by miter joints welded at the corners.

Above the table supporting frame are side bearing frame members 10 and 11 in the form of fabricated plates extending between columns I, 4 and 2, 3, respectively, which, as will later appear, form the bearings for transverse shafts and also have inwardly extending arms providing bearings for the end shafts atthe folding station and supports for other elements.

Similarly at a lower level horizontal frame members are provided for supporting bearings for other drive parts. A front transverse frame member 12 is joined at its ends by side longitudinal frame members 13 and 14 and two parallel intermediate longitudinal frame members 15 and 16. The rear ends of members 13 and 15 are. joined by transverse member 17 and the rear ends of members 14 and 16 are joined by member 18. Upright members or bosses 19, 20, 21 and 22 form the supporting bearings for longitudinal guide shafts, as will later appear.

At the bottom of the frame longitudinal and transverse angle members connect the four corner columns, the rear transverse member 23 being shown in Fig. 2, and the other members not appearing in the drawings. On these bottom structural members is a motor supporting plate 24 on which rests an electric motor 25, which drives the various movable parts, as will be described.

Over the rear end of the machine is supported a transversely disposed holder or magazine 26 for the blanks B. The magazine is tilted so as to support the blanks inclined with their longitudinal. dimension transverse of the machine and their front edges elevated. The retaining members for the blanks are spaced rods, there being two rear rods 27, two front rods 28 and one rod at each end numbered 29 and 30 for the left and right end rods, respectively.

The supports for these rods comprise two rear angle members 31, two front angle members 32, and side angle members 33 and 34, respectively. The members 31 are adjustably attached to a crosspiece 35 on two bracket arms 36 extending obliquely rearwardly from the columns 3 and 4, and the members 32 are adjustably attached to a cross piece 37 on two bracket arms 38 secured on top of the respective top longitudinal frame members 5 and 5a. The side angle members 33 and 34 are adjustably attached to the crosspiece 37, as shown in Figs. 1 and 2. The bottom of the magazine is open and the margins of the blanks rest on washers 39 supported on the bottom ends of the rods, the supports for the blanks being slight enough to allow them to be pulled off from the bottom by suction.

Table plates are supported on the front and rear frame members 6 and 7. As shown there are three table plates, a relatively wide center plate 40, and two narrow side plates numbered 41 and 42 on the left and right side, respectively. The side plates are spaced slightly from the center plate to provide slots for the travel of pusher fingers, as will appear, and for portions of their lengths the side plates are cut away on their inner edges to provide clearance for the folding fingers at the folding station. The side plates are also cut away on their outer edges at the folding station to accommodate hold-down fingers for the side and flaps which are on pivoted levers that are reciprocated in lateral planes in properly timed relation to the other folding operations, as will later appear.

Spanning the two lower inside longitudinal members 15 and 16 are two cross plates 43 and 44 which are bolted on top of the members. Those plates support hearings to which reference will later be made.

The carton delivery device for picking the blanks from the magazine and delivering them to the receiving station on the table consists of an invertible suction head having four suction cups arranged in a diamond pattern and movable up and down through motor driven means with means to reverse them during such movement so that they point up at the top of the movement and down at the bottom of the movement. They are shown in the former position in Fig. l and in the latter position in Figs. 2 and 5. The suction head is connected to a suction pump, aswill now be described.

The suction pump 45 is of the piston and cylinder type. The cylinder is hung by a baILand-socket joint from a bracket arm 46 which is integral with and extends out from the left top horizontal framemember 5 near its rear end. The piston stem 47 extends downwardly and is pivotally attached to a crank member. 48 on the outer end of shaft 49 which bears in bearings 50 secured on the tops of frame members 13 and 15. This shaft 49 delivers power to the various driven parts of the mechanism and is itself driven from-the motor 25 through sprocket chain 51 which runs over sprockets on the shaft 49 and on the armature shaft of the motor.

The suction head consists of a manifold 52 communicating with four cup tubes 53 on the end of each of which is a suction cup 54. An inflexible tube 54a connects the manifold with flexible tube 55 which leads to a T-connection 56 on top of the pump cylinder. The other side of the T-connection communicates with flexible tube 57 which leads to a normally closed tappet valve controlled port which is opened in properly timed sequences, as will be described.

The manifold 52 is attached to a rock shaft 58 which is connected to be moved up and down by themotor. The ends of rock shaft are provided with rollers 59 that are disposed in arcuate slots in guide plates 60, one guide plate being disposed in each side of the frame and attached at their lower ends to inwardly extending arms 61 on side plates and 11 and at their upper ends to similar arms on top frame members 5 and 5a. The slots in these side plates are concentric with the axis of a rock shaft 62 that bears at its ends in bosses on the end plates and has an enlarged, square midportion through which the pipe 54a slidably extends. In addition for guiding purpose two rods 63 carried by the shaft 58 extend slidably through the square portion of shaft 62.

The shaft 58 is reciprocated in the slots in the side plates by the motor through connecting rods 64 pivotally connected at their upper ends to the shaft 58 and having a block at their lower ends pivotally connected to cranks 65 on the outer ends of transverse shaft 66 which bears in bearings 67 bolted on the under sides of frame pieces and 16, respectively. Shaft 66 is driven from shaft 49 by sprocket chain 68 which runs over sprockets on shafts 49 and 66.

It will thus be seen that as the shaft 66 rotates the connecting rods 64 move the shaft 58 up and down and that the shaft as it follows the guide slots is caused to invert by reason of its coupling with the shaft 62. The parts are so arranged that the open end of the cups are presented to the bottom of the stack at the top of the stroke (Fig. 1) and to the table at the receiving station at the bottom of the stroke (Fig. 2).

The relief port for the tube 57 is controlled by a tappet valve 69. The arm for this valve is pivoted to valve head 70 in the face of which is the port forming the seat for the tappet valve. A coiled spring 71 which attaches the upper end of the valve arm to a block 72 biases the valve to closed position. A striker 73 on the shaft 49 strikes the tappet arm of the valve once on each rotation of the shaft and moves the tappet arm against its bias as the striker passes and opens the relief valve. This position of the striker is shown in Fig. 5.

The parts are set so that the successive steps are performed on desired timing. As shown in Fig. 1 the pump piston is at the top of its stroke as the cups approach the bottom of the stack and the piston is just reversing so as to reduce the pressure in the line as the cups are brought up into contact with the bottom blank. As the crank 65 passes over center and starts the down stroke of the head, the suction is sufficient to pull off the bottom blank. The continued rotation of crank 65 takes the head through its down stroke and the head is caused to invertthrough the connection with shaft 62. At the end of the down stroke the cups with the blank attached overhang the receiving station on the table and at this instant the striker 73 engages the tappet arm and opens the relief valve. The pump piston is reversed at the same time and not only is the suction broken but the upward movement of the pistoncreates a reverse pressure which positively deposits the blank, as indicated in Fig.5. The striker promptly passes off the tappet arm and the upward movement of the piston expels air through the cups until near the top of the stroke when the piston reverses and the delivery opera tion is repeated.

Steady fingers 74 overhang the table just ahead of the receiving station to hold the blanks in the Blane of the table as they are advanced to the folding station through pushing means which will next be described. These fingers are shaped wire members or rods of small diameter which are carried by a transverse bar 75 which is attached at its ends to side plates 10 and 11 and overhangs the table.

To transfer the blanks on the table and also to eject the erected boxes, pusher fingers which protrude up through the slots between the center plate 40 and two side plates 41 and 42 of the table are carried by a motor driven reciprocating carriage underneath the table. This carriage has a plate 76 from which side bars 77 extend toward the rear. Two guide rods 78 extend longitudinally of the machine underneath the table and are supported at their ends in the bosses 19, 21 and 20, 22, respectively. The carriage has bearing blocks 79 for slidably supporting the carriage on the rods 78, one pair of such blocks depending from the under side of plate 76 and the other pair being on the rear ends of the respective side bars 77.

A bifurcated boss 80 depending from the underside of plate 76 provides a wrist-pin connection for the con-. necting rod 81 which is motor operated to reciprocate the carriage. This rod 81 at its other end is pivotally connected to crank 82 on shaft 49, the length of which is proportioned to give the carriage the proper range of travel as the shaft 49 rotates. Thus the carriage moves back and forth on the rods 78.

Rear pusher fingers 83 are attached to the side bars and project up through the slots above the table top, one finger in each slot. Also pivotally supported on each side of the plate '76 is an ejector finger 84. These ejector fingers are bell crank shape having a depending arm 84a which engages limiting stops at the ends of its travel to rock the fingers on their pivots; and the other arm is shaped to a right angle the free leg of which rises and retreats above and below the table top as the finger is rotated on its bearing. This is so that the ejector fingers clear the blanks at the folding station as the carriage moves back to bring the rear fingers behind the next blank to be deposited, whereupon the ejector fingers may rise so as to be in position to eject the box formed from the blank at the folding station as the carriage moves forward to bring another blank into the folding station.

The stops engaged by the arms 84a comprise each a front roller 85 and a rear roller 86. The rollers 85 are mounted on the inner ends of rods 87 that are adjustably supported at their outer ends in the bosses 21 and 22, and the rollers 86 are mounted on the forward ends of rods 88 that are adjustably supported in depending arms 89 attached to the underside of plates 41 and 42, respectively.

The stops 85 and 86 are positioned to engage the arm 84a near the ends of its movements. Fig. 1 shows the position with the carriage started on its backward movement, the finger 84 having been rocked counterclockwise to withdraw the ejector leg. Fig. 5 shows the carriage on the start of its forward movement with the ejector leg protruding above the table. Both ejector fingers of course move in unison. The continued forward movement of the carriage will cause fingers 83 to advance the blank from the receiving to the folding station, while the ejector fingers move the erected box from the folding station onto chains 90 to be carried away, as shown in Fig. 3. Suitable means are provided to prevent the ejector fingers 84 from being moved beyond their proper extreme positions and from moving so fast as to rebound. As shown in Fig. 6, spring pressed friction washers restrain the freedom of pivotal movement and overhanging stops 91 limit the upward movement which results from the engagement of stop 86. (See Figs. 1, 5, 6, 9 and 10.)

Adjustable stops 92 are positioned on the side plates 41 and 42 to position the blanks at the folding station with respect to the longitudinal axis of the table. Means are also provided to adjust the blanks into proper lateral position for action upon them by'the folding fingers. These lateral adjusting means will now be described.

. On each end of the folding station are two pivoted lever arms 93 and 93a which are spaced so as to engage the blank opposite the side end flaps at each end, as shown in Fig. 3. They have an inward projection at their upper ends which overhangs the adjacent flap when the arms are at their inner position, this being the position shown in Figs. 3 and 6. They are made to oscillate on their pivots between this flap retaining position and the flap releasing position, shown, for example, in Pig. it). The two pairs of laterally adjusting arms are spaced just the length of the blanks and are positioned to bring the blanks into proper lateral position. These arms are reciprocated in proper timed relation by motor driven cam means.

Bearings 94 suspended underneath plate 44- (Fig. 1) provide rotatable support for a shaft 95 which is driven from shaft 66 by bevel gears 96. On the opposite end of the shaft 95 is cam 97 which engages a roller 98 on a rock lever 99.

This lever 99 is pivoted to hearing standard 190 on plate 43, and pitmans 101 and N2 are pivotally attached to the lever 99 on opposite sides of the pivot. These pitmans are connected to actuate the arms 93 and 93a.

Depending from each of plates 41 and 42 is a pair of bearing supporting arms 193 and spanning their lower ends is a rock sleeve 194 rotatable upon a shaft 105 (Fig. 6) supported at its ends in the arms 103. The lateral positioning arms 93 and 93a are secured to the sleeve 104 and arm 93 on each side has a downward extension to which the respective pitmans is pivotally attached and which is also attached to coiled spring we which has its other end connected to the frame as shown in Fig. 6, one to member 13 and the other to member 14, as shown in Fig. 4. V

The springs 1% act in opposition to the cam 97 and tend to hold the arms 93 and 93a to their inner position shown in Fig. 6, the roller 98 at this time being on the low part of the cam. Further rotation of the cam in a clockwise direction as viewed in Fig. 6 rotates the rock lever 99 in a clockwise direction to the position shown in Fig. 2 which withdraws the arms 93 and 9301 from the blank folding space and releases the side end flaps of the blank.

When the blank is moved into the folding station, plunger pads are brought down onto the bottom element 'B of the blank to hold it down on the table during the folding operation at the conclusion of which these holddown pads are raised to free the erected box for ejection. The construction and operation of these hold-down plungers will now be described.

There are two such hold-down plunger pads numbered 107 which are mounted on the ends of stems 108 (Fig. 6) that extend up through a depending sleeve 109 on the end of overhanging lever 110. A coiled spring 111 surrounds the sleeve and bears against a nut 112 on the stem and tends to hold the pad and stem distended while allowing them to yield, thus providing a yielding spring pressure on the blank. The arms 116 at their outer ends have laterally extending hub portions which bear rotatively on a stub shaft 113 spanning arms 114 on the respective side plates 1t and 11.

The arms 110 are moved about their pivots by a cam actuated vertical lever 115 which is pivotally attached at its upper end to the respective arm 110 and is raised and lowered by cam means.

At each end of the folding station is a short longitudinally extending shaft 116 which carries folding fingers and which will later be referred to in connection with the description of the folding operation. This shaft has on it a cam 117 which engages two rollers 118 on the lever 115 and positively moves the lever lengthwise up and down and thus raises and lowers the hold-down plunger pads, the two positions of the two pads being "8 indicated infull lines and broken lines in Fig. '6; The lever engages over the shaft 11s in an elongated opening to permit the movement of the lever.

The folding operation will now be described. The quadrangular space constituting the folding station is demarked or framed by four shafts which are rotatively supported above the table on the level of the side plates 10 and 11. There are two transversely extending side shafts 119 and 120 which bear in the side plates 10 and 11. Between these side shafts at each end of the folding station is an end shaft 116 already referred to. Power is delivered to shaft 119 by sprocket chain 121 which runs over sprockets on shafts 49 and 119. Shaft 119 is operatively connected to the other three shafts by bevel gears which drive the shafts in a one-to-one speed ratio in the proper directions. As shown in Fig. 3, the shaft 119 is connected to the end shafts 116 by bevel gears 122 and the end shafts are operatively connected to the side shaft 120 by bevel gears 123.

Secured on side shaft 119 are two pairs of folding fingers, one finger of each pair being within the end of the folded box and the other being just outside the end, the inner finger being for the purpose of engaging the side element of the blank at its adjacent end and raising that side, and the outer finger of the pair being for the purpose of turning in the side end flap on its end.

The inner finger of each pair is numbered 124 and the outer finger is numbered 125. The finger 124 is anchor shape providing a folding and blank engaging portion of considerable arcuate length. The blank engaging portion of finger 125 is an arcuate angular extension in the direction to engage the flap first with its free end, this flap engaging arcuate extension being also curved outwardly so that at its connected end its inner face is substantially in the plane of the end of the box. Thus it follows up the flap as it turns it in and brings it to a position at right angles to the side. The arcuate length of both fingers is enough to provide the necessary dwell. As shown in Fig. 9 finger 125 is adjustably attached to finger 124.

These fingers 124 and 125 may be termed the corner fingers. On each end shaft 116 are two fingers numbered 126 and 127, the former for raising the bottom end flaps E and E and the latter for turning in the side end flaps E and E so the side S is raised. The side shaft 120 has on it two folding fingers 128 which are adjustable in radial length, as shown in Fig. 9, and are disposed to engage the ends of side S and raise it.

The end shafts 116 bear in arms 129 and 130 that project in from the side plates 10 and 11. The end finger 127 has a foot portion 12711 the toe portion of which engages the respective end flap on the side S and turns it in as the fingers 128 are raising that side, and the heel portion of which engages the inner corner of the respective end flap on side S and opens the slit K for the reception of tongue T. This will now be described with reference to the several Figures 17 to 21, it being understood that the several fingers are set on their respective shafts to effect their respective functions at appropriate times.

The finger 126 is of the shape shown in Fig. 10, having a trailing arcuate angular extension which maintains contact with its bottom end flap. The finger 127 has a connection with finger 126 which permits of radial adjustment.

The folding fingers are so set that in the sequence of folding operations the first thing that occurs is the raising of the bottom end flaps on the two ends. Starting with Fig. 7 which shows in enlarged detail the left end of the blank shown in Fig. 3 and the associated folding mechanism, the finger 126 has raised the bottom end flap E to erect position and is continuing to dwell in holding contact. The side finger 124 has started to raise side S and the companion finger 125 has started to turn the sideend flap E; This is the stage shown in Fig; 17.

In the position of Fig. 8 finger 124 has raised S almost to erect position and finger 125 is continuing to turn flap E inward. This is the condition shown in Fig. 18.

Figs. 9 and 10 show the folding in substantially the same stage of progress as that of Fig. 8. Finger 125 is wiping up over flap E and because of its compound curve it is completing the inward folding of that flap. Finger 124, has not quite completed the erecting of side S and the toe of the foot 127a is just engaging the side end flap E Finger 128 has not yet engaged the side S Finger 126 will presently leave flap E Figs. 11 and 12 show the folding progressed to the stage shown in Fig. 19 in which finger 128 has engaged and partially raised side S and the toe part of foot 127a is turning the flap E into its right angle position. Finger 126 has moved off flap E, that fiap now being held by finger 125 which still dwells against the overlapping flap E The heel part of foot 127a is now about to engage flap E and as it wipes up it will press in the upper left hand corner of flap E and open slit K for the reception of tongue T on flap E Further movement of fingers 127 and 128 raises the side S to the position shown in Figs. 13 and 14 which is the condition shown in Fig. 20. The toe part of foot 127a has held flap E against the end of the box as finger 128 is raising side S and since the heel part has opened the slit, the tongue T is guided into the slit.

As the movement continues the fingers 128 push the side S to the erect position as shown in Figs. 15 and 16. Fingers 12S and 126 have left the box and the trailing part of finger 124 remains in engagement with side S and furnishes opposition to finger 128 in pushing flap E into its final position and completing the interlocking of the end flaps. The box is now completely erected as shown in Fig. 21 and fingers 84 will push it onto the conveyor 90a for removal.

It is apparent from the foregoing that the operation of the machine is one continuous integrated, repetitive process in which each step is properly timed in the sequence of steps.

As above stated, shaft 120 may be omitted and side S raised by fingers on the end shafts corresponding to fingers 125 if the machine is to be used to erect boxes having covers forming extensions of one side; the operating parts may readily be made adjustable to accommodate blanks of different sizes and other forms of component units will readily suggest themselves to those skilled in the art. While the illustrated machine is the one commercially employed, the invention comprehends equivalent mechanical structures within the scope of the appended claims.

What is claimed is:

1. A carton folding machine for forming a box from a blank creased and slitted to form a bottom, two side portions, a bottom end fiap at each end and a side end flap at each end of both side portions, the two side end flaps at each end being adapted to interlock, said machine comprising a table having a folding station, hold-down means for securing a blank at said station, rotative shafts mounted over the folding station and including a shaft parallel and proximate to each end of the blank and a shaft parallel and proximate to one side of the blank, a radial finger on the side shaft opposite each end of the adjacent side portion and adapted to engage the respective ends of and lift the side portion as the shaft rotates, another finger on the side shaft outside each said side lifting finger positioned and shaped to engage and fold in the respective side end flap as the side portion is lifted, a finger on each end shaft adapted to engage and lift the bottom end flap at its end as the end shaft rotates, means to lift the other side portion of the blank, a finger on each end shaft having a foot portion adapted to fold in the side end flaps on the said other side portion and efect interlock thereof with the other side end flaps at the 10 respective ends as said other side portion is lifted and power means for rotating the shafts.

2. A carton folding machine for forming a box from a blank creased to form side portions having foldable extensions constituting end flaps, one flap at each end having a slit in its top edge and the other flap having an interlocking tongue extension adapted to enter into the slit, said machine comprising a table having a folding station, rotative shafts mounted over the folding station and including a shaft parallel and proximate to each end of the blank, means operated in conjunction with said shafts to lift the side portions in succession, a radial finger on each end shaft having a foot portion adapted to engage the adjacent tongue bearing end flap with its toe portion and to engage the slitted end flap with its heel portion and open the slit and direct the tongue into the slit as the side portion having the tongue bearing flap is raised, and power means to operate the shafts.

3. A carton folding machine as claimed in claim 2 in which the means for lifting the side portions includes a shaft parallel and proximate to the side of the blank having the slitted end flaps and a radial finger on the shaft opposite each end of the adjacent side portion and adapted to engage the respective end of and lift the side portion as the shaft rotates and another finger on the side shaft outside each said lifting finger positioned and shaped to fold in the respective slitted end fiap as the side portion is lifted.

4. A carton folding machine for forming a box from a blank creased and slitted to form a bottom, two side portions, a bottom end flap at each end and a side end flap at each end of both side portions, the two side end flaps on one side portion having each a slit in its top edge and the two side end flaps on the other side portion having each an interlocking tongue extension adapted to enter into the slit of its opposing side end flap, said machine comprising a table having a folding station, four rotative shafts mounted over the folding station and constituting two side shafts parallel and proximate to the sides and two end shafts parallel and proximate to the ends of a blank disposed at said folding station, the shafts being geared together to rotate in unison, a radial side lifting finger on each side shaft disposed opposite each end of its respective side portion operative to engage and lift the side portion as the shaft rotates, an end flap folding finger outside each side lifting finger on the side shaft adjacent the slitted end flaps, a finger on each end shaft adapted to engage and lift the bottom end flap at its end as the end shafts rotate, a finger on each end shaft having a foot portion adapted to engage with its toe end and fold in the tongue bearing end flaps as their side portion is raised and to engage the slitted end flaps with their heels and open the respective slits and direct the respective tongues into their slits as the side with the tongue bearing fiaps is raised.

5. A carton folding machine as defined in claim 4 in which the side lifting fingers on the side shaft adjacent the slitted end flaps are angularly disposed in advance of the side lifting fingers on the other side shaft.

6. A carton folding machine as defined in claim 5 in which the bottom end flap lifting fingers are angularly disposed in advance of the end flap folding fingers on the side shaft.

7. A carton folding machine as defined in claim 6 in which the end flap folding fingers on the side shaft are angularly disposed in advance of the foot bearing fingers on the end shafts.

8. A carton folding machine as defined in claim 7 in which each of the bottom end flap operating fingers and each of the side lifting fingers on the side shaft adjacent the side having the slitted end flaps ha an arcuate extension adapted to dwell in contact with its blank portion after lifting it to erected position.

9. A carton folding machine as defined in claim 8 in which each end flap folding finger on the side shaft has r 11 an arcuate flap engaging portion shaped to a compound curve with its free end bearing outwardly.

10. In a carton folding machine having a folding station for blanks, a shaft mounted rotatively over one side of the station, and two pairs of blank folding fingers on said shaft, one finger of each pair being disposed within the side dimension of a blank and having at its outer end an arcuate engaging portion disposed in a plane transverse to the shaft, and the other finger of each pair having an angular extension disposed radially beyond the arcuate engaging portion of its companion finger and forming an end flap engaging portion curved outwardly from its attached end with its attached end in the plane of the outer face of the end of the folded carton.

11. In a carton folding machine, a shaft having two pairs of blank folding fingers as defined in claim in which the second mentioned finger of each pair is attached to its companion finger by means which provide for relative radial adjustment.

12. A carton folding machine comprising a table portion having a blank receiving station and a folding station, means to deliver blanks in succession to the receiving station, a guide support underneath the table, a carriage movably supported on the guide support, a motor driven crank operatively connected to the carriage to reciprocate the same, a pair of upstanding pushing elements at the rear end of the table extending through longitudinal slots in the table and adapted to engage the rear edge of a blank at the receiving station and transfer it to the folding station, laterally positioning levers at the respective ends of the folding station pivoted to oscillate in planes transverse to the movement of the carriage and having overhanging extensions at their upper ends adapted to engage and hold down the ends of a blank at the folding station, and means to oscillate the levers and move said extensions to and from overhanging position in timed relation to the movement of the carriage.

13. A carton folding machine comprising a table portion having a blank receiving station and a folding station, means to deliver blanks in succession to the receiving ing station, a guide support underneath the table, a carriage movably supported on the guide support, a motor driven crank operatively connected to the carriage to reciprocate the same, a pair of upstanding pushing elements at the rear end of the table extending through longitudinal slots in the table and adapted to engage the rear edge of a blank at the receiving station and transfer it to the folding station, a pair of carton ejecting members mounted at the forward end of the carriage and comprising each a bell crank lever pivoted on a transverse axis and having a downwardly extending operating arm and an angle arm including an ejector portion adapted to protrude through one of the slots and reciprocable above and below the table top as the lever is oscillated, and adjustablestops below the table in the path of the operating arm positioned to engage the operating arm at the ends of the travel of the carriage and reciprocate the bell crank lever and cause-the ejector portion to protrude above the table on the forward movement of the carriage and to withdraw below the table on the rearward movement of the carriage.

14. A carton folding machine comprising a table portion having a blank receiving station and a folding station, means to deliver blanks in succession to the receiving station, a guide support underneath the table, a cariiage movably supported on the guide support, a motor driven crank operatively connected to the carriage to reciprocate the'same, a pair of upstanding pushing elements at the rear end of the table extending through longitudinal slots in the table and adapted to engage the rear edge of a blank at the receiving station and transfer it to the folding station, laterally positioning levers at the respective ends of the folding station pivoted to oscillate in'planes transverse to the movement of the carriage and having overhanging extensions at their upper ends adapted to engage and hold down the ends of a blank at the folding station, means to oscillate the levers and move said extensions to and from overhanging position in timed relation to the movement of the carriage, a pair of carton ejecting members mounted at the forward end of the carriage and comprising each a bell crank lever pivoted on a transverse axis and having a downwardly extending operating arm and an angle arm including an ejector portion adapted to protrude through one of the slots and reciprocable above and below the table top as the lever is-oscillated,'and adjustable stops below the table in the path of the operating arm positioned to engage the operating arm at the ends of the travel of the carriage and reciprocate the bell crank lever and cause the ejector portion to protrude above the table on the forward movement of the carriage and to withdraw below the table on the rearward movement of the carriage.

' 7 References Cited in the file of this patent UNITED STATES PATENTS 989,797 Peters et al Apr. 18, 1911 2,112,121 Sidebotham Mar. 22, 1938 2,125,147 Bergstein July 26, 1938 2,158,335 Milmoe May 16, 1939 2,518,014 Inman Aug. 8, 1950 2,612,087 7 .Willbrandt Sept. 30, 1952 2,710,566 Ahlmeyer et al June 14, 1955 2,733,643 Fergnani 'Feb.' 7, 1956 

